Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car's computer has detected a problem with the sensor that checks the voltage of the pump that helps move the transmission fluid. It's like a helper pump for the car's gears, and the sensor is saying there's not enough power.
The P1A74 code indicates that the voltage sensor circuit for the electric or auxiliary transmission fluid pump is reading lower than expected. This could affect the pump's ability to function properly.
The electric or auxiliary transmission fluid pump is responsible for maintaining the proper pressure and flow of transmission fluid, especially in hybrid or electric vehicles. The voltage sensor monitors the electrical input to this pump. A 'circuit low' condition suggests that the sensor is detecting a voltage lower than the threshold required for optimal operation.
• Check Engine Light is on
• Transmission may not shift properly
• Reduced fuel efficiency
• Faulty voltage sensor
• Wiring issues such as shorts or open circuits
• Faulty transmission fluid pump
Voltage Sensor: A device that measures the electrical voltage in a circuit.
Transmission Fluid Pump: A pump that circulates transmission fluid to ensure proper lubrication and operation of the transmission.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connections to the voltage sensor.
• Test the voltage sensor for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace the faulty voltage sensor.
• Replace the transmission fluid pump if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Chevrolet Volt
• Toyota Prius
• Ford Fusion Hybrid
• Regular maintenance checks
• Ensure proper electrical connections
• Monitor transmission performance
Sensor Issue
• Have the vehicle inspected by a professional.
• Avoid heavy driving until the issue is resolved.
Check with your vehicle's manufacturer for warranty coverage on transmission components.
This code is more common in hybrid and electric vehicles due to their reliance on electric auxiliary pumps.
Moderate – It's important to address this issue to prevent potential transmission damage.
Driving with a faulty transmission pump can lead to further damage and may be unsafe.
• Vehicle at operating temperature
• Transmission in neutral or park
The electric/auxiliary transmission fluid pump is typically located near the transmission housing.
Q: Can I drive my car with this code?
A: It's not recommended to drive for long periods with this code active, as it could lead to transmission damage.
Q: How does this affect my car's performance?
A: You may experience shifting issues or reduced fuel efficiency.
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